Photographic-printing apparatus.



N0- 838A88. PATENTED OCT. 16, 1906. H. V; SUM-JENSEN.

PHOTOGRAPHIG PRINTING APPARATUS.

APPLIGATION rum) M130, 1905.

HANS VIGGO SUM-JENSEN, OF COPENHAGEN, DENMARK.

"PHOTOGRAPHIC-PRINTING APPARATUS.

Specification of Letters Patent.

Patented Oct. 16, 1906.

Application filed January 30, 1905. Serial No- 243,354.

To a whom [It may concern:

Be it known that I, HANS Vrceo SUM-JEN- SEN, physician, a citizen of the Kingdom of Denmark, residing at Copenhagen, Denmark, have invented certain new and useful Improvements in Photographic-Printing Apparatus, of which the following is a specifica tion.

The present invention relates to an improvement for photographic printing of drawings, photographic prints, and the like, the said improvement being that the rotating transparent internally-illuminated cylinder around which the negative and the photographic pa er are carried is hung freely in many small bands carried over rollers by which means with the exclusion of any other facilities a perfect close contact is attained between the negative and the photographic paper, The light source is a lamp in which gases form the luminous medium and where the light-arc extends uniformly through the whole length of the tube, which is somewhat larger than the length of the cylinder.

In the drawings,in which are shown an em bodiment of the invention, Figure 1 is a view showing the device seen from the end with the one end stand removed. Fig. 2 is a view of the same seen from the side a signifies a cylindric tube of some transparent materialas, for example, glass; f, one of the narrow endless bands ff f,,, in which the cylinder is hung free. After being carried around the cylinder the bands are carried over the rollers b, c, d, and e. The three first-named ones are single rollers somewhat longer than the cylinder, while the lastnamed is divided into a number of smaller rollers equal to the number of bands employed. The rollers e e a are each carried by an arm g, g and g the one end of which turns around a bolt 71, while the other end by draw-springs iis pulled downward. All the rollers and the arms are carried by the stand j. I" is a stand for the lamp 1.

The force driving the apparatus works on one of the rollers b or c, the negative m and the photographic paper a being carried in between the roller b and the cylinder a. When this is rotating in the direction of the arrow, the paper and negative will be carried along and having been carried around the cylinder they will appear between it and the roller 0.

The perfectly close contact between negative and paper is attained by the cylinder forcing them together through its weight against the bands f f f of which each are of no greater width than to allow of their fitting tightly everywhere to the cylinder, provided only that the width of the negative, which will generally stretch across a great many bands, is at least sufficient to equal at least the width of two bands. Through experiments it has been fully proved that a perfect contact between the bands is attained and that the intervening spaces do no harm.

As no other facilities are required to attain the perfect contact, the improvement is con sequently very simple, and therefore cheap to produce.

A further advantage secured by not using any fixed axle or interior supports is that any spiders or spokes which would be used in such a case to support the cylinder from the axle would ordinarily cross and interfere with the supporting means for the lamp, while in the present device this difficulty is wholly overcome.

Since the negative is not permanently attached to the cylinder, but merely held thereagainst by the bands, the negative freely issues at the completion of the photographic operation. At the same time the cylinder is in condition to receive a second negative in serted behind the hindmost end of the first one, so that the operation of feeding in nega tives and delivering the completed products proceeds continuously.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- In a photographic-printing apparatus, a plurality of horizontally-disposed guide-rolls, a band guided by said rolls and depending in a loop between them, a transparent cylinder hanging freely in said loop and supported wholly by said band, and a source of light within said cylinder.

In testimony that I claim the foregoing as my invention I have signed my name in presence of two subscribing witnesses.

HANS VIGGO SIIM-JENSEN.

Witnesses:

Vreeo BLoM, F. A. USJURG. 

